User-configurable person detection system, method and apparatus

ABSTRACT

A system, method and apparatus for configuring a person detection sensor. The person detection sensor may limit its transmissions in accordance with a pre-configured dwell time. The person detection sensor may receive a new dwell time from a personal communication device. When the new dwell time is received, it is stored in memory and is then used to regulate the number of transmissions of the person detection sensor in accordance with the new dwell time.

I. CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser.No. 17/198,444, filed on Mar. 11, 2021, which is a divisional of U.S.patent application Ser. No. 16/237,144, filed on Dec. 31, 2018, now U.S.Pat. No. 10,948,965.

II. FIELD OF THE INVENTION

The present invention relates to home security and, more particularly,to a system, method and apparatus to extend battery life for homesecurity sensors.

III. DESCRIPTION OF RELATED ART

Home security systems are very popular in the United States and abroad.Such home security systems typically comprise a security panel and anumber of sensors distributed around the home to detect unauthorizedentry and/or movement inside the home. For example, a home may have allof its doors and windows monitored by installing a wireless door/windowsensor onto each door and window of the home to detect unauthorizedentry, and one or more motion sensors installed at one or more pointsinside the home for detecting unauthorized movement within the home.Each of the sensors may transmit a wireless signal to the securitypanel, where the security panel may take further action once a signalhas been received from one of the sensors, such as to sound a sireninside the home or contact a remote monitoring facility.

In addition to the popularity of home security systems, home monitoringand control systems are now becoming widespread. Such systems allowusers to monitor their home security systems, turn lights on and offremotely, lock and unlock doors remotely, as well as to better controlhome heating and air conditioning systems. In the latter category,battery-powered, home occupancy sensors are being used to automaticallycontrol operation of heating and air conditioning systems when thesensors detect the presence of an occupant or not.

Occupancy sensors may suffer from greater battery drainage than motionsensors, due to the fact that occupancy sensors transmit a signal everytime occupancy is sensed. In contrast, motion sensors typically limitthe number of transmissions by using a preset “dwell time”, usually onthe order of between three and four minutes, that restricts transmissionto once per dwell time. Thus, the batteries in motion sensors tend tolast longer than batteries in occupancy sensors. This problem isexacerbated when an occupancy sensor is placed in a high-traffic area,such as an entry hallway or kitchen, for example. While battery life isusually better for motion sensors, a tradeoff occurs between batterylife and an accurate ability to know when a person is present or not.

Given that both motion sensors and occupancy sensors determine thepresence of people, and given the expense to purchase both types ofsensors, it might be desirable to use a motion sensor as a dual-purposesensor: a security motion sensor and an occupancy sensor. However, giventhe relatively long dwell time of motion sensors, accurate occupancydeterminations may suffer, as the dwell time prevents occupancy updateson a continuous basis.

It would be desirable, then, to combine traditional, battery-poweredmotion sensors with occupancy sensors to eliminate the need to purchaseboth types of sensors, and to reduce the number of battery-powereddevices in a home.

SUMMARY

A system, method and apparatus for configuring a person detection deviceis described herein. In one embodiment, an apparatus is described forconfiguring a dwell time of the apparatus, comprising a detector fordetecting a presence of a person in an area, a memory for storingprocessor-executable instructions and the dwell time, a transceiver forsending and receiving wireless signals, a processer coupled to thedetector, the memory and the transceiver, for executing theprocessor-executable instructions that causes the apparatus to receive,by the processor via the transceiver, a command from a personalcommunication device to change the dwell time, the command comprising anew dwell time, in response to receiving the command from the personalcommunication device to change the dwell time, store, by the processor,the new dwell time in the memory, determine, by the processor via thedetector, the presence of the person in the area, determine, by theprocessor, that a time greater than the new dwell time has elapsed sincethe transceiver previously transmitted a signal indicative of thepresence of a person in the area, and when the processor determines thata time greater than the dwell time has elapsed since the transceiverpreviously transmitted a signal indicative of the presence of a personin the area, transmit, by the processor via the transceiver, a newsignal indicative of the presence of the person in the area.

In another embodiment, a method for configuring a dwell time of a persondetection device is described, comprising receiving, by a processor viaa transceiver, a command from a personal communication device to changethe dwell time of the person detection sensor, the command comprising anew dwell time, in response to receiving the command from the personalcommunication device to change the dwell time, storing the new dwelltime in the memory, determining, by the processor via a detector, thepresence of a person in an area monitored by the person detectionsensor, determining, by the processor, that a time greater than the newdwell time has elapsed since the transceiver previously transmitted asignal indicative of the presence of a person in the area, and when theprocessor determines that a time greater than the dwell time has elapsedsince the transceiver previously transmitted a signal indicative of thepresence of a person in the area, transmitting, by the processor via thetransceiver, a new signal indicative of the presence of the person inthe area.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features, and advantages of the present invention willbecome more apparent from the following detailed description of thepreferred embodiments and certain modifications thereof when takentogether with the accompanying drawings in which:

FIG. 1 illustrates one embodiment of a system for configuring a dwelltime of a person detection device used to monitor an area in a home orbusiness;

FIG. 2 is a functional block diagram of the person detection device asshown in FIG. 1 ;

FIG. 3 is a functional block diagram of a personal communication deviceused to configure the person detection device as shown in FIG. 1 ; and

FIGS. 4A and 4B depict a flow diagram illustrating one embodiment of amethod for configuring the person detection device as shown in FIGS. 1and 2 .

DETAILED DESCRIPTION

This disclosure describes a person detection device specially configuredto act as either a security motion sensor, a home automation occupancysensor, or both. The motion sensor is initialized using an “app” on adevice that allows a dwell time of the motion sensor to be adjusted inaccordance with a function (i.e., security vs. occupancy) and aparticular location where the sensor is installed.

FIG. 1 illustrates a top, plan view of a system for configuring a dwelltime of a person detection device 102 used to monitor an area 100 in ahome or business. Area 100 generally comprises a room, hallway,entryway, or some other portion of a residence or business. Persondetection device 102 comprises a sensor for determining the presence,and/or absence, of one or more persons in area 100 in accordance withthe teachings herein. Person detection device 102 may comprise abattery-powered motion sensor using passive infra-red (PIR) detectiontechniques, as known in the art, to detect infra-red heat as a personmoves across area 100. Person detection device 102 may, alternatively orin combination, comprise an occupancy sensor, used to determine thepresence of one or more persons in area 100 using techniques such asultrasonic, infra-red, thermal, or other well-known techniques todetermine if a person is occupying area 100. Unlike traditional motion(PIR) sensors, occupancy sensors generally do not require movement of aperson in order to detect their presence.

Person detection device 102 may transmit a signal indicative of thepresence of a person to a personal communication device, such as tocentral controller 104, upon detection of a person in area 100, inaccordance with an adjustable dwell time stored within person detectiondevice 102, as will be explained in greater detail later herein. Centralcontroller 104 comprises a home security panel, gateway, hub or someother device that monitors person detection device 102, as well as othersensors and/or home monitoring and control devices, installed withinarea 100 or other areas of a home or business. Examples of centralcontroller 104 include a GC3 Security & Control panel sold by NortekSecurity and Control, Inc., a base station sold as part of an alarmsecurity kit by Ring, Inc., a Pulse® interactive touch screen panel soldby ADT, Inc. In other embodiments, controller 104 may not be used. Inthese embodiments, person detection device 102 is monitored by a remoteserver 110 in communication with person detection device 102 via awide-area network 108, such as the Internet, and a local-area network(LAN) 106. In the remaining disclosure, any reference to centralcontroller 104 may include reference to remote server 110. In someembodiments, central controller 104 comprises both security and homemonitoring and control functionality. Finally, central controller 104may communicate with remote server 110 via local-area network 106 andwide-area network 108 where central controller 104 lacks independentmeans to send alerts or other information externally to area 100.

When central controller 104 receives a signal from person detectiondevice 102, or some other security or home monitoring sensor, centralcontroller 104 may perform one or more actions, such as to contact aremote, security monitoring facility (not shown) via wide-area network108, or by some other means, such as via cellular communicationtechnology. Alternatively, or in addition, central controller 104 maycause a siren (not shown) inside of area 100, or elsewhere in anotherlocation inside a home or business, to sound, and/or a strobe light (notshown) to flash.

Person detection device 102 may be programmed remotely using a personalcommunication device 112. personal communication device 112 may comprisea fixed or mobile computing device, such as a laptop or desktopcomputer, or it may comprise a mobile phone, tablet computer, wearabledevice, or some other device capable of wireless communications withperson detection device 102, either directly or indirectly vialocal-area network 106 and/or wide-area network 108 (when personalcommunication device 112 is located outside of area 100 and out of rangeof local-area network 106) and also offering a user interface forprogramming person detection device 102. personal communication device112 is configured to run an executable software program that allows auser to program person detection device 102. personal communicationdevice 112 typically provides a user interface, where at least a dwelltime of person detection device 102 may be changed. In one embodiment,personal communication device 112 communicates with remote server 110,which stores account information for thousands, or millions, or users,each who have one or more person detection devices in their respectivehomes or businesses. In this embodiment, a user account may store acurrent dwell time of person detection device 102 as provided by a uservia personal communication device 112. The dwell time may then beprovided to person detection device 102.

FIG. 2 is a functional block diagram of one embodiment of persondetection device 102. In this embodiment, person detection device 102comprises a processor 200, a memory 202, a person detector 204, and atransceiver 206. It should be understood that the functional blocks maybe connected to one another in a variety of ways, that additionalfunction blocks may be used (for example, amplification or filtering),and that not all functional blocks necessary for operation of persondetection device 102 are shown for purposes of clarity, such as a powersupply.

Processor 200 is configured to provide general operation of persondetection device 102 by executing processor-executable instructionsstored in memory 202, for example, executable code. Processor 200typically comprises a general purpose processor, such as an ADuC7024analog microcontroller manufactured by Analog Devices, Inc. of NorwoodMass., although any one of a variety of microprocessors, microcomputers,microcontrollers, and/or custom ASICs selected based on size, cost,power consumption, computing power, and/or other factors.

Memory 202 is coupled to processor 200 and comprises one or morenon-transitory, information storage devices, such as RAM, ROM, flashmemory, or virtually any other type of electronic, optical, ormechanical information storage device. Memory 202 is used to store theprocessor-executable instructions for operation of person detectiondevice 102 as well as any information used by processor 200, such as adwell time that defines how often person detection device 102 maytransmit when a person is detected. Memory device 202 could,alternatively or in addition, be part of processor 200, as in the caseof a microcontroller comprising on-board memory.

Person detector 204 is coupled to processor 200 and comprises a sensorand related circuitry and, in some embodiments, firmware, to detect thepresence or absence of one or more persons in area 100. Person detector204 may comprise one or more passive infra-red (PIR) detectors (fordetecting motion of an infra-red emitting body), ultrasonic detectors(for detecting a doppler shift from a reflected body), heat or thermaldetectors (for determining a temperature change), carbon dioxide sensors(for detecting the presence of carbon dioxide), microwave sensors (fordetecting a doppler shift from a reflected body), a keycard detector(for determining when a hotel guest has inserted a hotel key card),and/or a camera (using firmware to detect a shape in the form of aperson).

Transceiver 206 is coupled to processor 200 and comprises circuitrynecessary to transmit and receive wireless signals from centralcontroller 104, local-area network 106 and/or personal communicationdevice 112. Such circuitry is well known in the art and may compriseBlueTooth, Wi-Fi, Z-wave, Zigbee, X-10, RF, optical, or ultrasoniccircuitry, among others.

FIG. 3 is a functional block diagram of one embodiment of personalcommunication device 112, showing processor 300, memory 302, userinterface 304, and one or more transceivers 306. It should be understoodthat the functional blocks shown in FIG. 3 may be connected to oneanother in a variety of ways, and that not all functional blocksnecessary for operation of personal communication device 112 are shown(such as a power supply), for purposes of clarity.

Processor 300 is configured to provide general operation of personalcommunication device 112 by executing processor-executable instructionsstored in memory 200, for example, executable code. Processor 300typically comprises one or more microprocessors, microcontrollers, orcustom ASICs that provide communications functionality to personalcommunication device 112 as well as to execute instructions that providean ability for personal communication device 112 to configure persondetection device 102 to change the dwell time of person detection device102.

Memory 302 is coupled to processor 300 and comprises one or morenon-transient information storage devices, otherwise referred to as oneor more processor-readable mediums, such as RAM, flash memory, orvirtually any other type of electronic, optical, or mechanicalinformation storage device. Memory 302 is used to store theprocessor-executable instructions for general operation of personalcommunication device 112 (for example, communication functionality) andfor providing a user interface to a user for configuring persondetection device 102 to change the dwell time of person detection device102.

User interface 304 is coupled to processor 300 and allows a user toconfigure person detection device 102. User interface 304 may compriseone or more pushbuttons, touchscreen devices, electronic displaydevices, lights, LEDs, LCDs, biometric readers, switches, sensors,keypads, microphones, speakers, and/or other human interface devicesthat present indications to a user or generate electronic signals foruse by processor 300 upon initiation by a user. A very popular userinterface today is a touchscreen device.

Transceiver 206 comprises circuitry necessary to wirelessly transmit andreceive information to/from personal communication device 112, such asone or more of a cellular transceiver, a Wi-fi transceiver, a Bluetoothtransceiver, a cellular data transceiver, an Ethernet adapter, and/orsome other type of wireless means for communications. In someembodiments, more than one transceiver is present, for example, acellular transceiver and a Wi-Fi transceiver. Such circuitry isgenerally well known in the art.

FIGS. 4A and 4B depict a flow diagram illustrating one embodiment ofmethod, or algorithm, performed by person detection device 102 andpersonal communication device 112, for configuring a dwell time ofperson detection device 102. It should be understood that in someembodiments, not all of the steps shown in FIG. 4 are performed and thatthe order in which the steps are carried out may be different in otherembodiments. It should be further understood that some minor methodsteps have been omitted for purposes of clarity.

The process begins at block 400, where a user launches an application onpersonal communication device 112 to configure person detection device102. The application may initiate a session with remote server 110 toaccess an account where information pertaining to person detectiondevice 102, and associated information such as an owner's name, address,phone number, account number, email address, etc., may be stored. Inother embodiments, personal communication device 112 communicates withperson detection device 102 either directly (i.e., using Bluetooth orBLE), or indirectly (i.e., via local-area network 106).

At block 402, processor 300 of personal communication device 112presents a user interface display to the user via user interface 304.The user interface display is typically a graphical user interface,allowing the user to determine a status of person detection device 102(such as whether person detection device 102 is connected to centralcontroller 104, an operating mode of person detection device (i.e.,“walk test”, normal), a current setting for the dwell time, an estimatedbattery life of person detection device 102, etc.) and also to allow theuser to make certain modifications to person detection device 102 (i.e.,to change the dwell time). The user interface display may comprise oneor more drop-down menus, slider bars, entry boxes, etc. to allow theuser to change the dwell time.

At block 404, the user modifies the dwell time using the user interfacedisplay on user interface 304. The user may wish to minimize the dwelltime to, for example, 2 seconds, for purposes of conducting a “walktest”. A walk test may be conducted upon initial installation of persondetection device 102 on a wall or ceiling, by walking in front of persondetection device 102 at various distances and angles, to see if persondetection device 102 detects movement of the user. During such a walktest, it is desirable to quickly determine if person detection device isable to detect the user without having to wait several minutes, as wouldbe the case with longer dwell times during a normal mode of operation.Thus, the dwell time may be reduced to something on the order of a fewseconds during a walk test.

A user may wish to increase the dwell time of person detection device102, for example to four minutes, when person detection device 102 willbe used as a motion sensor. It is generally desirable to limit thenumber of transmissions of motion sensors; otherwise, each time thatmovement is detected, a transmission will occur, thus draining thebattery relatively quickly. By changing the dwell time to 4 minutes,person detection device 102 is only capable of transmitting one motiondetection signal every 4 minutes, thus saving battery life.

On the other hand, the user may wish to change the dwell time of persondetection device 102, for example to one minute, when person detectiondevice 102 will be used as an occupancy sensor. It is generallydesirable that occupancy sensors be capable of transmittingoccupancy/non-occupancy signals at more frequent intervals than motionsensors, in order to better know whether a room remains occupied forpurposes of controlling lighting, heating/cooling, etc. By setting thedwell time at an intermediate time, such as between 30 seconds and twominutes, person detection device 102 acts more like an occupancy sensor,transmitting indications of movement/occupancy more often than withincreased dwell times.

In any case, an indication of the new dwell time is provided from userinterface 304 to processor 300.

At block 406, processor 300, in turn, generates a command to change thedwell time and causes the command to be transmitted to remote server 110and/or person detection device 102, via transceiver 306, which mayinclude an identification of a particular person detection device 102 tobe modified. The command may include the new dwell time, or the newdwell time may be transmitted in a separate message or command. Inanother embodiment, the new dwell time is not provided to remote server110 and/or person detection device 102 until the user is satisfied thatthe new dwell time will not have undesired battery life implications, asdescribed below.

At block 408, in one embodiment, processor 300 may estimate a remainingor expected battery life of person detection device 102, using the newdwell time. The remaining battery life may take into account how longperson detection device 102 has been installed, or how long since thebattery(ies) of person detection device 102 was/were changed. Theexpected battery life may provide an estimate of the battery lifeassuming that new batteries have been installed. Memory 302 may receivea standard battery life of person detection device 102 via remote server110 at some point during a setup process, identifying an expectedbattery life for a particular make and/or model of person detectiondevice 102 at a default dwell time, such as two minutes. As the dwelltime is increased from the default dwell time, processor 300 mayestimate the remaining or expected battery life, based on the defaultbattery life and the new dwell time. For example, if the expectedbattery life of person detection device 102 is 36 months using a dwelltime of two minutes, and the dwell time is increased to 3 minutes,processor 300 may determine an estimated or expected battery life of 48months, depending on factors such as the amount of power consumed byperson detection device 102 during transmission of signals indicative ofmovement/occupancy once every 3 minutes. Similarly, an estimate of theremaining or expected battery life may be determined by processor 300when the dwell time is decreased.

At block 410, remote server 110 may receive the command/new dwell timefrom personal communication device 112 and store the new dwell time inan associated database in accordance with the particular persondetection device 102 identified by personal communication device 112.Remote server 110 may then forward the new dwell time to persondetection device 102.

At block 412, processor 200 receives the command/new dwell time viatransceiver 206. Processor 200 may determine that the command comprisesan instruction to change a current dwell time store in memory 202 withthe new dwell time by comparing the command to a plurality of commands,such as a command to reset person detection device 102, a command toprovide the status of person detection device 102, a command to enterinto a walk test mode of operation from a normal mode of operation, orother commands. When processor 200 determines that the command is acommand to change the dwell time, processor 200 stores the new dwelltime in memory 202.

At block 414, processor 200 may determine a remaining or expectedbattery life for the battery(ies) that power person detection device102. In one embodiment, processor 200 measures a voltage of thebattery(ies) as person detection device 200 transmits a signal, ascurrent is drawn from the battery(ies) during transmission. The voltagelevel may be compared to an expected battery voltage when thebattery(ies) are new, and the deviation from the expected batteryvoltage indicates a remaining battery life.

In another embodiment, memory 202 may receive a standard battery life ofperson detection device 102 via remote server 110 at some point during asetup process, identifying an expected battery life for a particularmake and/or model of person detection device 102 at a default dwelltime, such as two minutes. As the dwell time is increased from thedefault dwell time, processor 200 may estimate the remaining or expectedbattery life, based on the default battery life and the new dwell time.For example, if the expected battery life of person detection device 102is 36 months using a dwell time of two minutes, and the dwell time isincreased to 3 minutes, processor 200 may determine an estimated orexpected battery life of 48 months, depending on factors such as theamount of power consumed by person detection device 102 duringtransmission of signals indicative of movement/occupancy once every 3minutes. Similarly, an estimate of the remaining or expected batterylife may be determined by processor 200 when the dwell time isdecreased.

At block 416, processor 200 may transmit the remaining or expectedbattery life to remote server 110 and/or personal communication device112 via transceiver 206.

At block 418, processor 300 in person detection device 102 receives theremaining battery life and may store the remaining battery life inmemory 302.

At block 420, processor 300 may display the remaining battery life tothe user via user interface 304 and the user interface display.

At block 422, the user may choose to again modify the dwell time if theuser determines that the expected or remaining battery life isunacceptable to the user. In an embodiment where processor 300determines the remaining or expected battery life, the new dwell timemay not be provided to processor 300 until the user is satisfied thatthe new dwell time will not adversely affect the batter life more thanthe user may tolerate, but trying a variety of new dwell times, and onlyproviding a final, new dwell time to processor 300, once the user issatisfied. This may be achieved by the user pressing a “submit” icon, orother, similar indication, displayed by user interface 304, once theuser has selected a desired dwell time.

At block 424, at some later time, processor 200 determines that a personis present in area 100 by evaluating signals from person detector 204.

At block 426, processor 200 determines an elapsed time since a previoussignal was transmitted, indicating that a person was within area 100.

At block 428, processor 200 compares the elapsed time from when aprevious signal was transmitted to the new dwell time to determine ifthe elapsed time is greater than the new dwell time.

At block 430, if the elapsed time is greater or equal to the new dwelltime, processor 200 causes a signal to be transmitted indicative of aperson in area 100, via transceiver 206.

At block 432, if the elapsed time is less than the new dwell time,processor 200 refrains from causing a signal to be transmittedindicative of a person in area 100, and processor continues to evaluatesignals from person detector 204 to determine if a person is presentwithin area 100, where blocks 422-432 are repeated.

Therefore, having now fully set forth the preferred embodiment andcertain modifications of the concept underlying the present invention,various other embodiments as well as certain variations andmodifications of the embodiments herein shown and described willobviously occur to those skilled in the art upon becoming familiar withsaid underlying concept. It is to be understood, therefore, that theinvention may be practiced otherwise than as specifically set forth inthe appended claims.

What is claimed is:
 1. A person detection device for configuring a dwelltime of the person detection device, comprising: a detector fordetecting a presence of a person in an area; a memory for storingprocessor-executable instructions and the dwell time; a transceiver forsending and receiving wireless signals; and a processer coupled to thedetector, the memory and the transceiver, for executing theprocessor-executable instructions that causes the person detectiondevice to: receive, by the processor via the transceiver, a new dwelltime from a personal communication device; in response to receiving thenew dwell time, estimate, by the processor, a remaining battery lifebased on the new dwell time; transmit, by the processor via thetransceiver, the estimated remaining battery life to the personalcommunication device; receive, by the processor via the transceiver, anindication from the personal communication device to use the new dwelltime; and replace, by the processor, the dwell time in the memory withthe new dwell time.
 2. The person detection device of claim 1, whereinthe processor-executable instructions comprise further instructions thatcause the person detection device to: determine, by the processor viathe detector, the presence of the person in the area; determine, by theprocessor, an elapsed time since the transceiver previously transmitteda signal indicative of the presence of a person in the area; and whenthe processor determines that the elapsed time is less than the newdwell time, refrain, by the processor, from transmitting a new signalindicative of the presence of the person in the area.
 3. The persondetection device of claim 1, wherein the processor-executableinstructions comprise further instructions that cause the persondetection device to: determine, by the processor, an elapsed time sincethe transceiver previously transmitted a signal indicative of thepresence of the person in the area; and when the processor determinesthat the second elapsed time is greater than the new dwell time,transmit, by the processor via the transceiver, a new signal indicativeof the presence of the person in the area.
 4. The person detectiondevice of claim 1, wherein the new dwell time comprises an incrementaltime in which to increase or decrease the dwell time by a predeterminedamount.
 5. The person detection device of claim 1, wherein the new dwelltime comprises a time period.
 6. The person detection device of claim 5,wherein the processor-executable instructions comprise furtherinstructions that cause the person detection device to: compare, by theprocessor, the time period to an upper dwell time threshold stored inthe memory; determine, by the processor, that the time period exceedsthe upper dwell time threshold; and transmit, by the processor via thetransceiver, an error message to the personal communication device whenthe processor determines that the time period exceeds the upper dwelltime threshold.
 7. The person detection device of claim 6, theinstructions for estimating a remaining battery life comprisesinstructions that causes the person detection device to: measure, by theprocessor, a battery voltage of the person detection device during atransmission by processor via the transceiver; compare, by theprocessor, the battery voltage to a stored battery voltage in thememory; and determining, by the processor, the remaining battery life asa result of comparing the battery voltage to the stored battery voltagein the memory.
 8. A method, performed by a person detection device, forconfiguring a dwell time of the person detection device, comprising:receiving a new dwell time from a personal communication device; inresponse to receiving the new dwell time, estimating a remaining batterylife based on the new dwell time; transmitting the estimated remainingbattery life to the personal communication device; receiving anindication from the personal communication device to use the new dwelltime; and replacing the dwell time storing in a memory with the newdwell time.
 9. The method of claim 8, further comprising: determiningthe presence of the person in the area; determining an elapsed timesince a signal was transmitted by the person detection device,indicative of a presence of a person in an area proximate to the persondetection device; and when the elapsed time is less than the new dwelltime, refraining from transmitting a new signal indicative of thepresence of the person in the area.
 10. The method of claim 8, furthercomprising: determining an elapsed time since the transceiver previouslytransmitted a signal indicative of the presence of the person in thearea; and when the second elapsed time is greater than the new dwelltime, transmitting a new signal indicative of the presence of the personin the area.
 11. The method of claim 8, wherein the new dwell timecomprises an incremental time in which to increase or decrease the dwelltime by a predetermined amount.
 12. The method of claim 8, wherein thenew dwell time comprises a time period.
 13. The method of claim 12,further comprising: comparing the time period to an upper dwell timethreshold stored in the memory; determining that the time period exceedsthe upper dwell time threshold; and transmitting an error message to thepersonal communication device when the time period exceeds the upperdwell time threshold.
 14. The method of claim 13, further comprising:measuring a battery voltage of the person detection device during atransmission by the person detection device; comparing the batteryvoltage to a stored battery voltage in a memory of the person detectiondevice; and determining the remaining battery life as a result ofcomparing the battery voltage to the stored battery voltage in thememory.